const mgh = document.querySelector('.mgh')
mgh.addEventListener('click', function () {
    alert('马国豪')
})

const yel = document.querySelector('.yellow')
yel.addEventListener('click', function () {
    this.style.backgroundColor = 'skyblue'
})

const lyw = document.querySelector('.lyw')
lyw.addEventListener('click', function () {
    alert('李运炜')
})